Guidelines for Good Practice of Water Reuse for Irrigation: Portuguese Standard NP 4434

Abstract

The growing number of municipal wastewater treatment plants in Portugal delivers about 500 million m3 of treated wastewater that is discharged in river and coastal waters, representing a pollutant load to receiving waters and yet the waste of water resources which could be successfully used for irrigation in agriculture, landscape, golf courses, water reservoirs for fire protection. Because water reuse can contribute to the economic development it must be stimulated by central, regional, and local authorities, but within the framework of good practices and their monitoring. This paper presents the new Portuguese standard NP 4434 that presents guidelines on water quality, irrigation practice, management of environmental impacts, protection of public and animal health and, aspects of control and monitoring.